A new method was created to determine arsenic in rice. To validate this method, a reference standard was used with a certified concentration of 2.1 ppm of Arsenic, with a standard deviation of 0.7 ppm . When analyzing the reference standard 7 times, with the new method, an average of 2.87 ppm was obtained with a standard deviation of 0.4 ppm. These results show that the new method Has it been validated? Does it have systematic errors? Has a precision similar to that of the reference standard

A new method was created to determine arsenic in rice. To validate this method, a reference standard was used with a certified concentration of 2.1 ppm of Arsenic, with a standard deviation of 0.7 ppm . When analyzing the reference standard 7 times, with the new method, an average of 2.87 ppm was obtained with a standard deviation of 0.4 ppm. These results show that the new method Has it been validated? Does it have systematic errors? Has a precision similar to that of the reference standard

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.17QAP

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Calculate the standard deviation for an element whose % in a sample were found to be20.8, 21.6, 22.1, 22.0, 23.3, 21.9 and 22.8%
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